//  (C) Copyright John Maddock 2019.
//  Use, modification and distribution are subject to the
//  Boost Software License, Version 1.0. (See accompanying file
//  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

// Contains Quickbook markup, using in Boost.Multiprecision.qbk section on Literals and constexpr, penultimate section
// on factorials.

#include "constexpr_arithmetric_test.hpp"
#include "nil/crypto3/multiprecision/cpp_int.hpp"
#include "nil/crypto3/multiprecision/integer.hpp"
#include "test.hpp"

template<class F, class V>
decltype(std::declval<F>()(std::declval<V>())) non_constexpr_invoke(F f, V v) {
    return f(v);
}

//[factorial_decl
template<class T>
constexpr T factorial(const T& a) {
    return a ? a * factorial(a - 1) : 1;
}
//]

template<class T, class U>
constexpr T big_mul(const U& a, const U& b) {
    using nil::crypto3::multiprecision::multiply;
    T result = T();
    multiply(result, a, b);
    return result;
}
template<class T, class U>
constexpr T big_add(const U& a, const U& b) {
    using nil::crypto3::multiprecision::add;
    T result = T();
    add(result, a, b);
    return result;
}
template<class T, class U>
constexpr T big_sub(const U& a, const U& b) {
    using nil::crypto3::multiprecision::subtract;
    T result = T();
    subtract(result, a, b);
    return result;
}
template<class U>
constexpr U div_qr_d(const U& a, const U& b) {
    using nil::crypto3::multiprecision::divide_qr;
    U result = U();
    U r = U();
    divide_qr(a, b, result, r);
    return result;
}
template<class U>
constexpr U div_qr_r(const U& a, const U& b) {
    using nil::crypto3::multiprecision::divide_qr;
    U result = U();
    U r = U();
    divide_qr(a, b, result, r);
    return r;
}
template<class T>
constexpr T do_bit_set(T val, unsigned pos) {
    using nil::crypto3::multiprecision::bit_set;
    bit_set(val, pos);
    return val;
}
template<class T>
constexpr T do_bit_unset(T val, unsigned pos) {
    using nil::crypto3::multiprecision::bit_unset;
    bit_unset(val, pos);
    return val;
}
template<class T>
constexpr T do_bit_flip(T val, unsigned pos) {
    using nil::crypto3::multiprecision::bit_flip;
    bit_flip(val, pos);
    return val;
}
template<class T>
constexpr T test_swap(T a, T b) {
    swap(a, b);
    a.swap(b);
    return a;
}

int main() {
    using namespace nil::crypto3::multiprecision::literals;

    typedef nil::crypto3::multiprecision::checked_int1024_t int_backend;
    typedef nil::crypto3::multiprecision::checked_int512_t small_int_backend;
    typedef nil::crypto3::multiprecision::checked_uint1024_t unsigned_backend;

    constexpr int_backend f1 = factorial(int_backend(31));
    static_assert(f1 == 0x1956ad0aae33a4560c5cd2c000000_cppi);
    constexpr unsigned_backend f2 = factorial(unsigned_backend(31));
    static_assert(f2 == 0x1956ad0aae33a4560c5cd2c000000_cppui);

    //
    // Test integer non-member functions:
    //
    constexpr small_int_backend si1 = (std::numeric_limits<small_int_backend>::max)();
    constexpr small_int_backend si2 = 239876;
    constexpr std::int32_t i = (std::numeric_limits<int>::max)();
    constexpr std::int32_t j = 239876;
    // Multiply:
    {
        constexpr int_backend i1 = big_mul<int_backend>(si1, si2);
        int_backend nc;
        multiply(nc, si1, si2);
        BOOST_CHECK_EQUAL(nc, i1);

        constexpr std::int64_t k = big_mul<std::int64_t>(i, j);
        std::int64_t ii;
        nil::crypto3::multiprecision::multiply(ii, i, j);
        BOOST_CHECK_EQUAL(ii, k);
    }
    // Add:
    {
        constexpr int_backend i1 = big_add<int_backend>(si1, si2);
        int_backend nc;
        add(nc, si1, si2);
        BOOST_CHECK_EQUAL(nc, i1);

        constexpr std::int64_t k = big_add<std::int64_t>(i, j);
        std::int64_t ii;
        nil::crypto3::multiprecision::add(ii, i, j);
        BOOST_CHECK_EQUAL(ii, k);
    }
    // Subtract:
    {
        constexpr int_backend i1 = big_sub<int_backend>(si1, -si2);
        int_backend nc;
        subtract(nc, si1, -si2);
        BOOST_CHECK_EQUAL(nc, i1);

        constexpr std::int64_t k = big_sub<std::int64_t>(i, -j);
        std::int64_t ii;
        nil::crypto3::multiprecision::subtract(ii, i, -j);
        BOOST_CHECK_EQUAL(ii, k);
    }
    // divide_qr:
    {
        constexpr small_int_backend i1 = div_qr_d(si1, si2);
        small_int_backend nc, nc2;
        divide_qr(si1, si2, nc, nc2);
        BOOST_CHECK_EQUAL(nc, i1);

        constexpr std::int64_t k = div_qr_d(i, j);
        std::int32_t ii, ij;
        nil::crypto3::multiprecision::divide_qr(i, j, ii, ij);
        BOOST_CHECK_EQUAL(ii, k);
    }
    // divide_qr:
    {
        constexpr small_int_backend i1 = div_qr_r(si1, si2);
        small_int_backend nc, nc2;
        divide_qr(si1, si2, nc, nc2);
        BOOST_CHECK_EQUAL(nc2, i1);

        constexpr std::int64_t k = div_qr_r(i, j);
        std::int32_t ii, ij;
        nil::crypto3::multiprecision::divide_qr(i, j, ii, ij);
        BOOST_CHECK_EQUAL(ij, k);
    }
    // integer_modulus:
    {
        constexpr int i1 = integer_modulus(si1, 67);
        small_int_backend nc(si1);
        int r = integer_modulus(nc, 67);
        BOOST_CHECK_EQUAL(r, i1);

        constexpr std::int32_t k = nil::crypto3::multiprecision::integer_modulus(i, j);
        std::int32_t ii(i);
        r = nil::crypto3::multiprecision::integer_modulus(ii, j);
        BOOST_CHECK_EQUAL(r, k);
    }
    // powm:
    {
        constexpr small_int_backend i1 = powm(si1, si2, si2);
        small_int_backend nc(si1);
        nc = powm(nc, si2, si2);
        BOOST_CHECK_EQUAL(nc, i1);

        constexpr std::int32_t k = nil::crypto3::multiprecision::powm(i, j, j);
        std::int32_t ii(i);
        ii = nil::crypto3::multiprecision::powm(ii, j, j);
        BOOST_CHECK_EQUAL(ii, k);
    }
    // lsb:
    {
        constexpr int i1 = lsb(si1);
        small_int_backend nc(si1);
        int nci = lsb(nc);
        BOOST_CHECK_EQUAL(nci, i1);

        constexpr std::int32_t k = nil::crypto3::multiprecision::lsb(i);
        std::int32_t ii(i);
        ii = nil::crypto3::multiprecision::lsb(ii);
        BOOST_CHECK_EQUAL(ii, k);
    }
    // msb:
    {
        constexpr int i1 = msb(si1);
        small_int_backend nc(si1);
        int nci = msb(nc);
        BOOST_CHECK_EQUAL(nci, i1);

        constexpr std::int32_t k = nil::crypto3::multiprecision::msb(i);
        std::int32_t ii(i);
        ii = nil::crypto3::multiprecision::msb(ii);
        BOOST_CHECK_EQUAL(ii, k);
    }
    // bit_test:
    {
        constexpr bool b = bit_test(si1, 1);
        static_assert(b);

        constexpr bool k = nil::crypto3::multiprecision::bit_test(i, 1);
        static_assert(k);
    }
    // bit_set:
    {
        constexpr int_backend i(0);
        constexpr int_backend j = do_bit_set(i, 20);
        static_assert(bit_test(j, 20));

        constexpr int ii(0);
        constexpr int jj = do_bit_set(ii, 20);
        static_assert(nil::crypto3::multiprecision::bit_test(jj, 20));
    }
    // bit_unset:
    {
        constexpr int_backend r = do_bit_unset(si1, 20);
        static_assert(bit_test(r, 20) == false);

        constexpr int jj = do_bit_unset(i, 20);
        static_assert(nil::crypto3::multiprecision::bit_test(jj, 20) == false);
    }
    // bit_unset:
    {
        constexpr int_backend r = do_bit_flip(si1, 20);
        static_assert(bit_test(r, 20) == false);

        constexpr int jj = do_bit_flip(i, 20);
        static_assert(nil::crypto3::multiprecision::bit_test(jj, 20) == false);
    }
    // sqrt:
    {
        constexpr int_backend r = sqrt(si1);
        small_int_backend nc(si1);
        nc = sqrt(nc);
        BOOST_CHECK_EQUAL(nc, r);
        constexpr int_backend r2 = sqrt(si1 * 1);
        BOOST_CHECK_EQUAL(nc, r);

        constexpr int jj = nil::crypto3::multiprecision::sqrt(i);
        int k = i;
        k = nil::crypto3::multiprecision::sqrt(k);
        BOOST_CHECK_EQUAL(jj, k);
    }
    {
        // swap:
        constexpr small_int_backend r = test_swap(si1, si2);
        static_assert(si1 == r);
    }
    {
        // gcd:
        constexpr int_backend i(si1), j(si1 / 3);
        constexpr int_backend k = gcd(i, j);

        int_backend ii(i), jj(j);
        BOOST_CHECK_EQUAL(k, gcd(ii, jj));

        constexpr unsigned_backend ui(i), uj(j);
        constexpr unsigned_backend uk = gcd(ui, uj);
        unsigned_backend uii(ui), ujj(uj);
        BOOST_CHECK_EQUAL(uk, gcd(uii, ujj));

        constexpr int_backend l = lcm(i, j);
        BOOST_CHECK_EQUAL(l, lcm(ii, jj));
        constexpr unsigned_backend ul = lcm(ui, uj);
        BOOST_CHECK_EQUAL(ul, lcm(uii, ujj));
    }
    return boost::report_errors();
}
